The Planet Earth Singers perform in many styles. That’s exactly what Amman had in mind when he formed the group back in 2004, after retiring as Ball State University’s director of choral activity following some 22 years there.
"Amman forms Planet Earth Singers to celebrate the music of the world,"
Illinois Wesleyan University Magazine: Vol. 18
, Article 10.
Available at: https://digitalcommons.iwu.edu/iwumag/vol18/iss1/10